I bet you never thought goldfish could be the missing link to sustainable food production. Well, you better take a second look at these humble little guys, because if you’ve ever wanted to grow your own food—without a lot of space, soil, or chemical fertilizers—then a goldfish just might be your new best friend (along with several million bacterial ‘acquaintances’). This is the beauty of aquaponics.
First things first: aquaponics is NOT hydroponics. Hydroponics, while very efficient at growing plants without soil, relies on a sterile environment and a lot of energy input and external regulation, especially in the form of synthetic chemical fertilizers that are usually made from petroleum. Therefore, most hydroponic endeavors, while innovative, are resource intensive and not sustainable. Aquaponics, on the other hand, mimics natural biological systems to create a thriving ecosystem that eliminates the need for synthetic fertilizers, while still maximizing efficiency of plant growth. You don’t need any soil, and you need very little space. It all comes back to the fish and the bacteria. While backyard aquaponics systems typically use feeder fish like goldfish, commercial systems tend to use marketable fish like Tilapia, which they can harvest and sell along with their food crops, resulting in an even more lucrative, yet still sustainable, food production system.
The basics of an aquaponics system go like this: 1) the fish create waste that bacteria in the water consume, which releases valuable nutrients like nitrogen and phosphorus; 2) this nutrient rich water is ‘fed’ to plant roots to nourish the plants and help them grow; 3) by removing these nutrients from the water, the plants have ‘purified’ the water which is then re-circulated back to the fish. The water is naturally purified, and the plants are naturally fed, in this fairly closed system. The bacteria do the essential dirty work in between. The only input needed is fish food, which you typically have to buy. However, even this part of the system may soon become completely sustainable, because biologists Ken Nielson and Radu Popa of River Road Research are developing fish feed as one by-product of their black soldier fly project (discussed in my last post).
Grow Your Own
David Rosenstein of EVOFarm, based in Santa Monica, explained the biological processes behind aquaponics in a lecture as part of the Future of Food program I attended on Catalina Island this past week. David, an unimposing young entrepreneur with a passion for sustainable food, founded EVOFarm as a way to fight back against our current chemical laden, diesel powered, polluted and corrupt industrial-agricultural complex.
Through years of tinkering and tireless perfection, David and his team have created aquaponics systems that successfully provide abundant harvests at all scales, from small backyard units for families, to larger scale systems for schools and for commercial sale of crops. Using aquaponics, you can harvest crops (like lettuces, kale, tomatoes, chard, spring onions, etc.) up to ten times per year, and produce anywhere from six to thirty times the amount of food per acre that you could reasonably harvest from a soil based system. Revolutionary! David estimates that the dollar value of this food per acre is over 1 million dollars, which would be unheard of in a soil system.
The yields from aquaponics aren’t just remarkably higher, but they are created without the use of harmful synthetic fertilizers, are very water efficient (water is continually recycled in the system, with minimal evaporation), can exceed organic standards, taste amazing, and result in local food security. You could literally have an aquaponics system in every backyard, as well as larger community-run systems. This would help reduce the number of ‘food miles’ of the fresh fruits and vegetables that we eat, lowering our impact on climate change as well as our reliance on industrial agriculture. Plus, it’s a fun hobby!
Rome wasn’t built in a day…but this aquaponics system was!
It’s actually super easy to build your own aquaponics system—and that’s just what we did (well, I mainly watched the students build it while I tagged along to take pictures). David, along with USC graduate student Ryan Lesniewski, showed us that with a few basic materials and a small investment, you can have your system up and running in a day, and be ready to plant all the crazy heirloom seeds you want by the end of the week.
After you get water into the system, you add some compost tea (aka liquid worm poo) to help grow the beneficial bacteria, which sets the biological basis for the system. Then you can add your fish, place your plants on top, and watch nature take its course. You need to monitor the water level and quality fairly regularly, but other than that the system is very low maintenance day-to-day (though if you like tinkering, there are myriad variables you can mess around with, like nutrient sources, quantities, water flow rates, etc.).
In fact, Ryan has been experimenting with these types of variables as part of his PhD research, which is focused on the development of aquaponics. He has become a self-made expert in a novel field where there aren’t really any experts yet. By growing seedlings in his closet and building aquaponics test systems on his tiny downtown L.A. balcony, Ryan has already learned a lot about the ins and outs of growing plants sans soil, knowledge that he is applying to the larger-scale systems he experiments with out on Catalina.
Meanwhile, David has been designing eye-pleasing backyard vertical aquaponics systems for local distribution, perfectly sized for backyard patios and balconies. His real dream, though, is to establish large-scale aquaponics farms to grow food for commercial sale, and revolutionize (there’s that word again!) the agricultural industry.
If you have a passion for growing (or eating) healthy, fresh, mouth-wateringly good food, than you have a vested interest in the growth of aquaponics. I know that I’m a convert, and can’t wait to help out with future projects like these that engage people in growing their own food to save money and build food security—and hopefully have fun!
What if we could produce most of the food we eat right in our backyards, without using any chemicals or soil, and without producing any waste to go to the landfill? Wouldn’t that be amazing? Sounds like some idealistic Ecotopia scenario, but guess what? It is 100% possible!
That’s the groundbreaking fact I learned this week after attending a five-day program on Catalina Island focused on the Future of Food. Topics ranged from food waste and biological farming to backyard aquaponics and sustainable fisheries. One of the very first ideas presented by guest speakers was so jaw-droppingly revolutionary that it has the potential to change our entire food AND energy systems!
Send in the Flies
This innovative idea that is about to blow your mind is the brainchild of two established biology professors: Ken Nielson (of USC) and Radu Popa. These inspiring individuals may have invented a way to solve two of society’s biggest problems: eliminating large-scale food waste and providing abundant renewable energy to the masses. It sounds unbelievable, but their system is beautiful in its (relative) simplicity—and it all relies on insects. Black soldier flies, to be exact.
Ken calls his project the Black Soldier Fly alternative, or BSFA for short. He and Radu have developed a process in which they can convert nearly all food waste (whether from your home kitchen or an industrial food producer) to a rich insect feed for the black soldier fly larva. The feed is created using Bokashi fermentation, where a combination of aerobic and anaerobic bacteria break down the waste and release valuable nutrients in the process—not so unlike the methods used to produce fermented vegetables and drinks, like that fancy Kombucha you picked up from Whole Foods. As a result, valuable nutrients from the waste like calcium, nitrogen, and phosphorus are made available for re-use.
Just think about that for a second. Eliminating all food waste. Currently, Americans throw away about 40% of the food we buy each year, most of which ends up in local landfills, rotting and releasing greenhouse gases like methane. It costs the city of Los Angeles alone $64 million dollars a year in tipping fees to dump the 1.3 million tons of food waste Angelenos produce. Of course, reducing how much we throw out in the first place would be the best approach, but changing individual and industrial behavior will not happen overnight, so in the meantime we need to find better ways to eliminate this waste. Composting helps, but can only accommodate about 10-15% of total food waste, meaning the rest still gets thrown out. All of that food waste could instead be converted to insect feed and actually result in a net financial gain. Here’s how:
The nutrient-rich liquid that results from fermentation is fed to the fast growing soldier fly larvae. A portion of these larvae will be harvested as animal feed for chickens and other livestock, reducing the need to rely on fishmeal, soybean oil, and other unsustainable feed sources. The larvae waste (i.e. poop) can also be used as a rich fertilizer for plants and crops (or aquaponics systems, which I’ll discuss in my next post). But the truly miraculous aspect of this endeavor comes from something else the larvae produce: melanin.
That’s right, melanin—the stuff that regulates our skin and hair color, as well as the coloration of animals, such as the spots on a squid. It turns out that melanin is a powerful electricity conductor, making it a perfect substance to use in rechargeable batteries. Yet you’ve probably never seen a melanin battery in your local store. Why? Normally, melanin is very expensive to produce, much too costly to support a lucrative battery industry. That is, it was too expensive. Ken and Radu have discovered that black solider fly larvae produce relatively large quantities of melanin in their bodies, which can be extracted for human use, including for batteries. Melanin batteries would be completely organic, non-toxic, and biodegradable. No more reliance on precious metals and harmful battery acids.
When Ken first described this to his audience in the lecture hall on Catalina, the concept didn’t seem to sink in. So he repeated his conclusion: Through the BSFA process, we can eliminate food waste, produce rich animal feed and fertilizer, and most importantly, create a renewable source of melanin to produce completely biodegradable batteries. An entirely closed-loop system! Melanin batteries could be used effectively to store energy produced by renewable sources such as wind and solar—energy sources that are difficult to store with current battery technology.
Even the adult black soldier flies provide financial value to the system. Once they reproduce and lay eggs, they die. Their exoskeletons are high in chitin, a polymer with numerous commercial uses including wastewater treatment, bandages, a binder for dyes, fabrics, and adhesives, and more.
Ken and Radu have established a private venture, partnered with a company called River Road Research, to continue to tweak and expand this system—which Ken wryly describes as the first example of insect domestication—and are hoping to soon trial it on a massive scale by working with food producers and cities in the near future. Their hope is to turn food waste into a lucrative commodity that ultimately benefits cities, agricultural production, livestock production, and the renewable energy sector.
In my next post I’ll discuss the concept of aquaponics, another sustainable approach to food production and waste elimination that is set to change the way we think about food. We humans may have a fighting chance thanks to some brave and cunning individuals!